1. Field of the Invention
This invention, in the capacity of a new drug, possessing several applications in clinics, is concerned with the chemical substance of the following formula: ##STR1## in which R represents hydrogen or an acetyl residue.
The chemical denomination of the compound is therefore: 17 alpha-ethynyl(5 alpha), 2-androsten,17 beta-ol (and its 17 beta-acetate).
2. Description of the Prior Art
Several authors and, namely, M. HUFFMAN (U.S. Pat. No. 2,996,524) J. A. EDWARDS and A. BOWERS (Chemistry and Industry, 1961, p. 1962-1963) and D. POMONIS & al. (Cancer Chemotherapy Reports, 1962, Sept. 31-32), described a process for obtaining a substance to which they thought they could attribute the structure and chemical formula of 17 alpha-ethynyl(5 alpha), 2-androsten,17 beta-ol (and its acetate), possessing properties that:
stimulate the reticulo-endothelial system,
inhibit the gonads by suppressing the pituitary gonadotrophins.
When establishing the analytical file of a drug containing the substance prepared according to the teaching of M. Huffman in Example 8 of U.S. Pat. No. 2,996,524, as demanded by the Health Authorities of all countries, in order to be assured of the purity of the said substance, the applicant discovered that this process led, not to the pure product (I), but to a mixture of this product (I) with its delta-3 isomer (II), the latter in varying proportions from one batch to another, but always in unacceptable proportions, e.g. roughly 20%. ##STR2##
On further analytical study, the applicant also discovered that the raw material used by the method described by Huffman in U.S. Pat. No. 2,996,524 and improperly designated as 17-keto(5 alpha), 2-androsten, was itself a mixture of isomers delta-2 and delta-3 and this was the reason it was not possible for the final product to be pure.
The identical polarity of these two isomers makes their separation by the classical methods of chromatography impossible; now, it is well-known that the usual methods of preparation of steroids of this chemical family inevitably lead to mixtures of isomers delta-2 and delta-3 which are not possible to separate (J. FAJKOS & al., Czech.Chem.Comm., 1959,24: 3115-3135; P. D. KLIMSTRA, J.Med.Chem, 1965, 8: 45-52).
Health Authorities do not accept products for therapeutical use unless their purity is invariable and compatible with the safety of the patients. The applicant was therefore obliged to continue his investigations until he discovered the method of preparative purification as embodied by this invention and which enabled him to eliminate the delta-3 isomer from the raw material.